Reciprocal natural hybridization between Lycoris aurea and Lycoris radiata (Amaryllidaceae) identified by morphological, karyotypic and chloroplast genomic data

Background Hybridization is considered as an important model of speciation, but the evolutionary process of natural hybridization is still poorly characterized in Lycoris. To reveal the phylogenetic relationship of two new putative natural hybrids in Lycoris, morphological, karyotypic and chloroplast genomic data of four Lycoris species were analyzed in this study. Results Two putative natural hybrids (2n = 18 = 4 m + 5t + 6st + 3 T) possessed obvious heterozygosity features of L. radiata (2n = 22 = 10t + 12st) and L. aurea (2n = 14 = 8 m + 6 T) in morphology (e.g. leaf shape and flower color), karyotype (e.g. chromosome numbers, CPD/DAPI bands, 45S rDNA-FISH signals etc.) and chloroplast genomes. Among four Lycoris species, the composition and structure features of chloroplast genomes between L. radiata and the putative natural hybrid 1 (L. hunanensis), while L. aurea and the hybrid 2, were completely the same or highly similar, respectively. However, the features of the cp genomes between L. radiata and the hybrid 2, while L. aurea and the hybrid 1, including IR-LSC/SSC boundaries, SSRs, SNPs, and SNVs etc., were significantly different, respectively. Combining the karyotypes and cp genomes analysis, we affirmed that the natural hybrid 1 originated from the natural hybridization of L. radiata (♀) × L. aurea (♂), while the natural hybrid 2 from the hybridization of L. radiata (♂) × L. aurea (♀). Conclusion The strong evidences for natural hybridization between L. radiata (2n = 22) and L. aurea (2n = 14) were found based on morphological, karyotypic and chloroplast genomic data. Their reciprocal hybridization gave rise to two new taxa (2n = 18) of Lycoris. This study revealed the origin of two new species of Lycoris and strongly supported the role of natural hybridization that facilitated lineage diversification in this genus. Supplementary Information The online version contains supplementary material available at 10.1186/s12870-023-04681-2.


Background
Lycoris Herb.(Amaryllidaceae) is a herbaceous perennial plant.The genus consists of more than twenty species and mainly distributes in eastern Asia, particularly in China, among which L. aurea and L. radiata are the most widespread species [1][2][3].Its bulb is rich in alkaloids, which is of important medicinal value such as tumorsuppressing and anti-malarial etc. [4].At the same time, flowers of this genus are diverse in shape and colour such as pink, red, white, yellow and multicolor etc., it has been used as an ornamental plant for centuries [5].
During field investigations of germplasm resources of Lycoris in Hunan and Hubei Province etc., China, we found two new natural variant populations of Lycoris with cream or chalky yellow flower in the distribution area of L. radiata and L. aurea, which have never been reported in these regions, and speculated that the two variations might represent undescribed taxa based on the observation of flower shape and colour.In this study, the living bulbs of the two new variant populations, L. radiata and L. aurea distributed in the same region (Yuanling County) were collected and studied on the karyotypes by CPD staining (combined PI and DAPI), fluorescence in situ hybridization (FISH) and chloroplast genomes by high-throughput sequencing etc. in order to reveal the interspecific relationships of the four Lycoris species, which could provide a scientific basis for the phylogenetic relationships and karyotype evolution of Lycoris.

Morphology comparison
The mainly morphological characteristics of L. radiata (Fig. 1a), L. aurea (Fig. 1b), putative natural hybrid 1 (Fig. 1c-e) and putative natural hybrid 2 (Fig. 1f-h) were shown in Fig. 1 and Table 1.As shown in Table 1, leaf widths of L. radiata, L. aurea, natural hybrid 1 (L.hunanensis) and hybrid 2 were 0.9, 3.2, 1.5, and 1.8 cm respectively.The flower colors of the hybrid 1 and hybrid 2 were gradually changing from pink or pale yellow in bud to cream or chalky yellow with few scattered red stripes in mid-anthesis respectively, and also the mature fruits and seeds have not been observed etc., suggesting that the two new natural variant taxa might be hybrid generations of L. radiata and L. aurea.

Karyotype analysis
CPD staining patterns and 45S rDNA-FISH signals in four Lycoris species were shown in Fig. 2, and their karyotype features including chromosome morphology, karyotype, CPD staining bands, DAPI bands, and 45S rDNA-FISH bands were shown in Fig. 3 and Table 2.
The karyotype parameters of L. radiata were shown in Supplementary Table S1.Its chromosomes were 2n = 22, including 12 st-type and 10 t-type chromosomes (Fig. 3a), and the ratio of the lengest/shortest chromosome(L/S) was 1.73.The average haploid total chromosome length (TCL) was 115.61 μm.The values of intrachromosomal asymmetry index (A 1 ) and interchomosomal asymmetry index (A 2 ) were 0.811 and 0.063, respectively.Its karyotype formula was 2n = 2x = 22 = 10t + 12st, with 4A Stebbins' karyotype asymmetry type.As shown in Fig. 2a, four red CPD bands in the terminal regions of short arms of chromosome 3, 4, 9 and 10 were detected respectively, but positive DAPI signals were absent in the chromosomes of L. radiata.Similarly, four red 45S rDNA-FISH signals (Fig. 2b) in the same regions of the four chromosomes were detected respectively, indicating that the CPD staining regions were also 45S rDNA-FISH signal sites in L. radiata.
The karyotype parameters of L. aurea were shown in Supplementary Table S2.Its chromosomes were 2n = 14, including 8 m-type and 6 T-type chromosomes (Fig. 3b), with the L/S ratio 2.45.The TCL was 145.95 μm.The values of A 1 and A 2 were 0.438 and 0.041, respectively.Its karyotype formula was 2n = 2x = 14 = 8 m + 6 T, 2B type.As shown in Fig. 2c, each of six T-type chromosomes had a red CPD band in the terminal centromeric point of chromosome 9, 10, 11, 12, 13 and 14, and also possessed a positive DAPI band in every pericentromeric regions of the six chromosomes respectively.At the same time, six red 45S rDNA-FISH signals stained in the same points of the six T-type chromosomes were detected respectively (Fig. 2d).Besides, four red 45S rDNA-FISH signals were also found in the median centromeric regions of a pair of m-type homologous chromosome 7, 8, and in the pericentromeric regions of a pair of T-type homologous chromosome 13, 14, respectively.
The karyotype parameters of natural hybrid 1(L.hunanensis) were shown in Supplementary Table S3.Its chromosomes were 2n = 18, including 4 m-, 3 T-, 6 st-, and 5 t-type chromosomes (Fig. 3c), with the L/S ratio 3.50.The TCL was 128.88 μm.The values of A 1 and A 2 were 0.719 and 0.052, respectively.Its karyotype formula was 2n = 2x = 18 = 4 m + 6st + 5t + 3 T, 3B type.As shown  a Fruit and seed of the putative natural hybrid 1 (L.hunanensis) have not been observed during cultivation.The traits of fruit and seed described in L. hunanensis [20] were inaccurate, which were made correction and amended in this study.Five plants (three leaves each plant) each sample were selected to determine morphological traits   S4.Its chromosomes were also 2n = 18, including 4 m-, 3 T-, 6 st-, and 5 t-type chromosomes (Fig. 3d), with the L/S ratio 4.31.The TCL was 129.69 μm.The values of A 1 and A 2 were 0.723 and 0.030, respectively.Likewise, its karyotype was also formulated as 2n = 18 = 4 m + 6st + 5t + 3 T, 3C type.As shown in Fig. 2g and h, the karyotype features of the hybrid 2, including CPD bands, DAPI bands and 45S rDNA-FISH signals etc., were as same as those of the hybrid 1 respectively.For example, each of the five chromosomes from 5 to 9 had a red CPD band in the centromeric points/regions respectively, in which the three T-type chromosomes also possessed a positive DAPI band in the pericentromeric regions respectively, etc.The other karyotype features of the hybrid 2 were displayed in Table 2 and would not be described here.

Basic feature of the four chloroplast genomes in Lycoris
The circular chloroplast genomes of the four Lycoris species were 158,405-158415 bp in size (Fig. 4), consisting of a pair of inverted repeat (IR, 26,733 bp), separated by large single copy (LSC, 86,596-86,598 bp) and small single copy (SSC, 18,342-18,351 bp) regions.Of these, the size of L. radiata and natural hybrid 1 (L.hunanensis), including LSC, SSC, IR and protein coding gene (PCG) regions, was the same, but they were slightly different from L. aurea and natural hybrid 2 in these regions (Table 3).Their cp genomes all contained 137 genes, including 87 PCGs, 42 tRNA genes and 8 rRNA genes.These genes of the four samples were completely consistent in functional classification, including 44 photosynthesis related genes (e.g.rbcL, ndhA, atpA, etc.), 80 transcription and translation related genes (e.g.rpl2, rps2, rpoA, rrn5, trnA-UGC, etc.), 6 others genes (e.g.matK, accD, ccsA, etc.), and 7 unknown function gene such as ycf1, ycf2, etc.Of these genes, 26 genes (e.g.petB, atpF, ndhA, etc.) and 2 genes (ycf3, clpP) contained 1 and 2 introns respectively in the four Lycoris cp genomes   (Table 4), suggesting the high conservation of chloroplast genes in the genus.

Comparisons of IR-LSC/SSC boundaries in the four Lycoris taxa
The circular structures of the cpDNA genomes of the four Lycoris taxa made four boundaries among LSC, SSC and IR, which were LSC-IRB, IRB-SSC, SSC-IRA, and IRA-LSC (Fig. 5).As shown in Fig. 5, among the four cp genomes, the genes and shrinkages or expansions of the IR boundaries were the same at the LSC-IRB, SSC-IRA and IRA-LSC borders.For example, the LSC-IRB borders of the four Lycoris samples were within the rps19, where the gene was 34 bp and 176 bp in the IRB and LSC regions respectively, and the IRA-LSC borders of them were all between the rps19 and psbA, their distances from the borders being 3 bp and 86 bp respectively.The IRB-SSC boundaries of the four samples were on the ndhF and ycf1, 107 bp ndhF spanned the IRB-SSC regions duplicated at the IRB regions in the four species, but there were minor differences at the ycf1 gene of the IRB-SSC regions of the four genomes, namely, 41 bp ycf1 of the IRB regions duplicated at the SSC regions in L.
aurea and natural hybrid 2, 35 bp of the gene duplicated in L. radiata and natural hybrid 1 respectively.Therefore, among the four Lycoris taxa, the genes and features of the IR boundaries were the completely same between L. aurea and natural hybrid 2, L. radiata and natural hybrid 1 respectively, suggesting that the putative natural hybrid 1 and hybrid 2 were more recently related to L. radiata and L. aurea, respectively.

SSR analysis
The chloroplast simple sequence repeats (cp SSRs) of the four Lycoris taxa were analyzed in this study.The numbers and types of the cp SSRs in these samples were shown in Supplementary Table S5.There were 58, 58, 63, and 63 SSRs in the L. radiata, natural hybrid 1, L. aurea, and natural hybrid 2 cp genomes, respectively.Six types of nucleotide repeats, including mononucleotide, dinucleotide, tri-nucleotide, tetra-nucleotide, penta-nucleotide and compound sequence, were detected in the four Lycoris taxa.Among the different unit sizes, the mononucleotide was the most frequent, accounting more than 55% of all types in the samples, in which base T and A were the primary elements, only one C motif in L. aurea

Table 4 Functional classification of chloroplast genes of four samples in Lycoris
The number of genes in parentheses a, b, c represent the gene has two, three and four, respectively.and natural hybrid 2, and two C in L. radiata and natural hybrid 1, but no G in the four samples.The numbers and types of the cp SSRs in L. radiata and the hybrid 1 were almost the same except for one different mononucleotide repetition, i.e. the former "(A) 10" and the latter "(A) 11" in the start site 30,544 bp, while only two repetitions differed in these SSR characteristics of L. aurea and the hybrid 2, including the mononucleotide repetition "(T) 14" and "(T) 13" in the start site 23,149 bp, the penta-nucleotide "(GGAAA)3" and "(CGAAA)3" in the start site 111,168 bp, respectively.However, these SSR characteristics of the hybrid 2 were significantly different compared with L. radiata.and the hybrid 1.For example, nine mononucleotide repetitions of cp SSRs in L. aurea and the hybrid 2, including "(T)11" (3701 bp) and "(A)10" (8381 bp) etc., were missing in L. radiata and the hybrid 1, respectively.At the same time, six mononucleotide repetitions of L. radiata and the hybrid 1, including " (A) 11" (14,137 bp) and "(A)10"(33,464 or 33,465 bp) etc., were missing in L. aurea and the hybrid 2, respectively.
Therefore, the results suggested that the putative natural hybrid 1 and hybrid 2 were more recently related to L. radiata and L. aurea, respectively.

SNV analysis
To reveal the differences of cp genomes in the four Lycoris species, interspecific comparisons were performed using Lycoris radiata (MN158120) plastome previously reported as the reference sequence (Table 5).As shown in Table 5, there were 150, 115, 151, and 138 SNPs in L. aurea, natural hybrid 1, hybrid 2, and L. radiata respectively, a total of 190 SNPs in the four samples.Of these SNPs, there were 36 and 120 same SNP sites between L. aurea and the hybrid 1, L. aurea and the hybrid 2 respectively, 103 and 30 same SNP sites between L. radiata and the hybrid 1, L. radiata and the hybrid 2 respectively.There were significant differences in the variation sites of the four cp genomes, including 50-82 SNPs located in 26-29 genes, 6-9 short insertions and 11-22 short missing fragments.Compared to the control (MN158120),  the bases CA (113,368-113,369 bp) and GT (58,741-58,742 bp) were inserted in the ycf1 gene of L. aurea and rbcL gene of L. radiata respectively, but not changed in these genes of the hybrid 1; the base G was mutated to A (78,820 bp) in the gene petB of L. radiata and the hybrid 1.Hence, these results showed that sequence variations between L. radiata and the hybrid 1 (L.hunanensis), L. aurea and the hybrid 2 were minor respectively, indicating the affinities and distances among the four Lycoris species.

Phylogenetic analysis
The UPGMA dendrogram of the four Lycoris species was generated based on average Euclidean distances in this study (Fig. 6).As shown in Fig. 6, dissimilarity values between taxa ranged from 0.014 to 0.039.Of these Lycoris species, L. radiata and putative natural hybrid 1 (L.hunanensis) were clustered into a clade while L. aurea and natural hybrid 2 were clustered into the other clade, indicating that their relationships between L. radiata and natural hybrid 1, L. aurea and natural hybrid 2 were much closer, respectively.In order to explore the interspecific relationships of the four samples and phylogenetic relationships of Lycoris species, the phylongenetic tree was constructed by maximum likelihood analysis based on complete cp genomes of 18 Lycoris species (Fig. 7).Narcissus poeticus (NC_039825) was selected as outgroup in this study.As shown in Fig. 7, 18 Lycoris species were clustered into three clades, Narcissus poeticus (outgroup) formed an alone branch.Among these samples, L. aurea, L. radiata (OR069402), L. radiata (MK353219), two natural hybrids, L. incarnate and L. chinensis were clustered into the second clade, indicating that the seven Lycoris species had a closer relationships in Lycoris.Especially between L. radiata and natural hybrid 1 (L.hunanensis), L. aurea and natural hybrid 2 could be divided into a minor branch in the second clade respectively, suggesting that interspecific relationships between L. radiata and natural hybrid 1 (L.hunanensis), L. aurea and natural hybrid 2 were much closer respectively.Obviously, the clusters of the four Lycoris species derived from the phenetic and chloroplast genomic data respectively were completely consistent, sufficiently indicating that the result of their interspecific relationships was correct and reliable.

Discussion
The karyotype evolution and phylogenetic relationship of species were complex and ambiguou, but some mechanisms, including Robertsonian fusion and fission, as well as hybridization etc., were well accepted [7,[21][22][23].Hybridization and polyploidization were considered as important models of speciation in this genus [6,17,24,25].In the phylogenetic tree, L. flavescens (NC_063555), L. sanguine (NC_047453), L. sprengeri (MN158986) and L. haywardii (NC_069836) were clustered into the third clade, furthermore, the first two and the latter two could be divided into a minor branch respectively, indicating that they had a closer relationships in Lycoris.Thus, hybrid origins about L. haywardii and L. flavescens etc. [16,17] were supported by chloroplast genome evidence.Of 18 Lycoris species, L. aurea, natural hybrid 2 and L. radiata (MK353219) could be divided into a minor branch in the second clade, suggesting that interspecific relationships of the three taxa were much closer in Lycoris.L. straminea was considered a descendant of Lycoris chinensis and Lycoris radiata var.pumila [1,26,27].L. straminea (2n = 19) and L. hunanensis (2n = 18) were of similar species based on morphological features such as leaf shape and flower colour etc. [20], however, they were clustered into different clades in Lycoris, indicating that there was obvious differences between morphology and cp genomes classification.
Theoretically, L. radiata (2n = 22 = 10t + 12st) and L. aurea (2n = 14 = 8 m + 6 T) could produce gametes with the karyotype compositions (n = 11 = 5t + 6st) and (n = 7 = 4 m + 3 T) by the meiosis respectively, and the F 1 progeny with the karyotype (2n = 18 = 4 m + 6st + 5t + 3 T) was produced by the fertilization uniting the male and female gametes.In our study, the two hybrid progenies with the karyotype composition (2n = 18 = 4 m + 6st + 5t + 3 T) were found in natural habitats (Table 2) and the representative heterozygosity features of karyotype were detected and affirmed, including four karyotypes (m, st, t, and T), 18 chromosomes etc., indicating that the two variant taxa of Lycoris originated from their hybridization of L. radiata and L. aurea in terms of karyotype.Judging from the absence of mature fruits and seeds, the two hybrid generations were sterile, which might be related to their compound karyotype compositions with m-, st-, t-, and T-type chromosomes, causing the failure of chromosomes pairing properly at meiosis [28].
This study showed that the corresponding chromosome features in the two hybrids, including special CPD bands and 45S rDNA-FISH signals etc., were all found in the chromosomes of their diploid parents (L.radiata and L. aurea).For example, 2 t/st-type chromosomes labeled by red CPD staining bands (one per chromosome) and especially only one m-type chromosome (number 1 in Fig. 2f and number 4 in Fig. 2h) labeled by a 45S rDNA-FISH signal (red) at the same sites in the two hybrids respectively, separated from a pair of m-type chromosomes (number 7 or 8 in Fig. 2d) of diploid parent (L.aurea), were detected in our study.And also three T-type chromosomes from their parent (L.aurea), with the positive DAPI signals in the two hybrids, were all detected at the same points (Table 2), suggesting that the putative natural hybrid 1 and the hybrid 2 possessed the heterozygosity features of the diploid parents (L.radiata and L. aurea), which were completely supported by the cp genome sequence analysis in this study (Figs.4,5,6;Tables 3,4,5).In general, these results in this study strongly supported that natural hybridization was an important model of species origin and karyotype evolution in Lycoris.
The chloroplast genome was relatively stable and genetically conserved because it possessed an independent genome from the mother, and played an indispensable role in elucidating interspecific relationship etc. [29][30][31].In this study, the results showed that a total of 137 genes were all annotated, including 87 PCGs, 42 tRNAs, and eight rRNAs, with 158,405-158415 bp sizes of the complete cp genomes in L. aurea, L. radiata, the putative natural hybrid 1 and the hybrid 2 (Table 3).These were consistent with the previous studies about cp genomes (137 genes) of L. chinensis, L. anhuiensis, and L. aurea reported by zhang et al. [8], suggesting that the cp genomes of Lycoris were highly conserved in structure.However, there was a significant difference from the 127 genes of the L. aurea chloroplast genome reported by Peng et al. [32], explaining that there was obvious variations of cp genomes among different populations in L. aurea.Of the four samples, compositions and structures of the chloroplast genomes in L. radiata and the putative natural hybrid 1, including their basic features, boundary genes, SSRs, and SNPs etc. (Table 5), were almost the same, suggesting that genetic relationship between the two species was closely related.Combining the karyotype analysis results in this study, we affirmed that the putative natural hybrid 1 (L.hunanensis) originated from the natural hybridization of L. radiata (♀) × L. aurea (♂).Similarly, the composition and structure features of the chloroplast genomes in L. aurea and the putative natural hybrid 2 were almost the same (Table 5, Fig. 5), suggesting their closer genetic relationship.Similarly, we also affirmed that the putative natural hybrid 2 originated from the hybridization of L. radiata (♂) × L. aurea (♀).

Conclusion
We found strong evidences for reciprocal natural hybridization between L. radiata (2n = 22) and L. aurea (2n = 14) by fluorescence in situ hybridization (FISH) and high-throughput sequencing etc., which gave rise to two new taxa (2n = 18) of Lycoris including the putative natural hybrid 1 (L.hunanensis) and hybrid 2, possessing their parental heterozygosity features in morphology, karyotype and chloroplast genome.This study revealed the origin of two new species of Lycoris and strongly supported the role of natural hybridization that facilitated lineage diversification in this genus.

Measurement of major morphological traits
The measurements of the morphological traits were conducted in different growth and development periods because the special feature of Lycoris is the absence of leaves while flowering.The morphological parameters of these samples, including flower colors in different anthesis and leaves (e.g.length, width) etc., were measured in August and December of the same year, respectively.Flower colors were quantified according to the standard of international color card.Five healthy and strong plants (three leaves each plant) from each sample were randomly selected to determine morphological traits, averaged and standard deviations were calculated in this study.

Karyotype analysis CPD staining and fluorescence in situ hybridization (FISH) of the chromosomes
The chromosome preparations of the four Lycoris species and CPD staining were performed as previously described [12] with minor modification in this study.In brief, the root tips were fixed in methanol: acetic acid (3:1) for 3 h after treatment with the α-bremnaphthalene at 28 ℃ for 4 h, and macerated with an enzyme mixture at 28 ℃ for 3 h.The well-spread chromosome preparations were used to perform CPD staining and FISH [33].The chromosome preparations were stained with 4' , 6-diamidno-2-phenylindole (DAPI) etc..The chromosomes and hybridization signals were observed by Olympus BX60 fluorescence microscope etc.

Sample collection, DNA extraction, and sequencing
Five healthy and strong plants from each sample were randomly selected to analyse chloroplast genomes in this study.The fresh leaves of the four samples in Lycoris were collected, flash frozen in liquid nitrogen, and stored at − 80 ℃ for DNA extraction.Genomic DNA was isolated using the Plant Genomic DNA Kit (Shanghai, China) according to the instructions, and its quality was examined using NanoDrop 2000 (Thermo Fisher Scientific, USA) etc. Highquality DNA was used for libraries' construction and sequencing, which was sequenced at Illumina Hiseq 2500 (Illumina, USA) using 2 × 150 two-end sequencing strategy with an insert size of 300 bp for highthroughput sequencing etc.
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Fig. 1
Fig. 1 The flowers of four taxa of Lycoris investigated in this study.a Lycoris radiata; b Lycoris aurea; c-e putative natural hybrid 1 (L.hunanensis), including bud (c), flower in early anthesis (d) and in mid-anthesis (e); f-h putative natural hybrid 2, including bud (f), flower in early anthesis (g) and in mid-anthesis (h)

Fig. 2
Fig. 2 Chromosomes of four Lycoris species stained with CPD and 45S rDNA-FISH.a, b are CPD staining pattern (red signals) and 45S rDNA-FISH signals (red) of chromosomes in L. radiata, respectively.c, d are CPD pattern and 45S rDNA-FISH signals (red) of L. aurea.e, f and g, h are the hybrid 1 and 2, respectively.Scale bars: 10 μm.Five cells in five different individuals of each sample were detected

Fig. 3
Fig. 3 The chromosome morphology and karyotypes of L. radiata (a), L. aurea (b), the hybrid 1 (c) and the hybrid 2 (d).T Terminal centromeric point.t terminal centromeric region.st subterminal centromeric region.m median centromeric region.Scale bars: 10 μm.Five cells in five different individuals of each sample were detected

Fig. 5
Fig. 5 Comparison of the borders of large single copy (LSC), small single copy (SSC), and inverted repeat (IR) regions among 4 Lycoris germplasm chloroplast genomes.c means distance cross over IR border.d means distance from IR border in this picture

Fig. 6 Fig. 7
Fig. 6 UPGMA dendrogram based on average Euclidean distances among the four Lycoris species

Table 1
Morphological characteristics of the four samples in Lycoris

Table 2
Karyotype features of four taxa in LycorisT Terminal centromeric point.t terminal centromeric region.st subterminal centromeric region.m median centromeric region.S short arm.CEN centromeric.PCEN pericentromeric.TER terminal.AT Stebbins' karyotype asymmetry type.A 1 intrachromosomal asymmetry index.A 2 interchomosomal asymmetry index.TCL average haploid total chromosome length.Five cells in five different individuals of each sample were detected Fig.4 Chloroplast genome map of the four samples in Lycoris

Table 5
Chloroplast genome variation sites of four samples in Lycoris